American horological journal, devoted to practical horology (1869)
Miller, George B · New York, G. B. Miller · leaf 197
e rounded extremity of the wire, bend-ing it to a position exactly perpendicular overthe centre. Having fixed the face of the board in atruly horizontal position, with the centreon the southerly side, commence to observe,about two hours before noon, the points atwhich the extremity of the shadow of… … A right line joining the two points on thesame circle will be an approximate east andwest line ; therefore, if the second line, joiningthe two points on each of the several circlesobserved, be bisected, the perpendicular, com-mon to them all, ajjd passing through thecentre, as per figure (1), will…
Clocks and watches
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![An illustration from L'optique divisée en trois livres : ou, l'On démontre d'une maniere aisée tout ce qui regarde 1. la propagation & les proprietez de la lumiere. 2. La vision. 3. La figure & la disposition des verres qui servent à la perfefectionner [sic] (1682)](https://img.insideoutlibrary.com/img/200/ia-loptiquedivise00ango-77-8.webp)
